Sentrol Industrial GuardSwitches are non-contact, magnetic devices consisting of a switch and a magnet actuator. They are extremely tolerant of misalignment and the build-up of dirt, grease and other contaminants. The typical air gap between actuator and switch is 0.5" to 1.0". This allows easy installation and a margin for the usual "settling out" shift that occurs in machine guard doors and gates. GE Interlogix GuardSwitches actuate through wood, aluminum, stainless steel or any other nonferrous material. This allows the interlock switches to be concealed in the machine for added protection against tampering. In addition, all switching elements are hermetically sealed, so they can be installed in dirty or corrosive environments.